For your kids, I would suggest all the party games. Rayman Raving Rabbids, Warioware Smooth Moves and Mario Party 8. These are great because you can play with them and totally keep up with them. (although that may require you to pick up a third Wii mote and Nunchuk so you can play with them heh). Wii is totally great for leveling the playing field between age groups.
And pssh it's great for grown-up parties too :P
__________________
|